On Thursday night, Trout (21 years, 16 days) became the youngest player since at least 1901 to record 40 steals and 20 homers in a season.
Trout swiped his 40th base in the third inning of a 14-13 win over the Red Sox at Fenway Park. Cesar Cedeno accomplished the feat in 1972 at 21 years, six months and one day.
The center fielder also leads the American League with a .345 average, 99 runs and 1.011 OPS.
"All those stats don't matter unless you reach the playoffs," Trout said. "But it's been pretty surreal."
Trout is in the midst of a rookie campaign for the ages. He leads all rookies this year with 24 homers, 72 RBIs and 45 walks.
He went 3-for-6 with two runs and two RBIs on Thursday. In a three-game sweep of the Red Sox, Trout had six hits, three runs and two steals.
"Mike Trout is terrific," Red Sox manager Bobby Valentine said. "He does everything you want a baseball player to do."
With one more homer, Trout will become the youngest player ever with at least 25 homers and 40 stolen bases in a single season. Cedeno also holds that distinction, doing it in 1973 at the age of 22.
If Trout continues to hold his batting average, he'll become the first player in Major League history to hit at least .340 with 20 homers and 40 steals.
"He's so professional that you would never know he's 21," Angels veteran outfielder Torii Hunter said. "He smiles at everybody, he talks to everybody the same. That's what I really enjoy about Mike Trout."
Austin Laymance is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.